How to Annotate a PDF Online for Free
Reviewing a document usually means marking it up - highlights, notes, arrows pointing at the problem. Here's how to do all of it in a browser.
Reviewing a document on paper means a highlighter, sticky notes, and arrows scrawled toward whatever needs attention. Reviewing a PDF digitally can do all of that directly in a browser, without printing anything or installing dedicated software.
What you can add
- Highlights - marking a passage of text directly, the digital equivalent of a highlighter
- Sticky notes - a comment attached to a specific spot without altering the page content itself
- Freehand drawing - circling something or sketching a quick note by hand
- Arrows and shapes - pointing directly at what you're referring to, or boxing off a section
- Text boxes - typed comments placed anywhere on the page
How to annotate a document
- Open the PDF in an online editor.
- Choose the annotation type you need - highlight, note, shape, or freehand - from the toolbar.
- Mark up the document as you review it, adjusting anything that's off before moving on.
- Export the annotated file once you're done, ready to send back or file away.
Reviewing a document with someone else
Annotations work well for sending feedback on a document without altering its actual text - the recipient sees exactly what you flagged and where, while the original content stays intact underneath the markup.
Frequently asked questions
What kinds of markup can I add to a PDF, beyond just highlighting?
A full-featured browser-based editor typically supports highlights, sticky notes, freehand drawing, arrows, shapes (rectangles, circles, speech bubbles), and text boxes - covering most of what document review actually needs.
Can I remove or adjust an annotation after adding it?
Yes - annotations stay editable and can be repositioned, resized, or deleted right up until you export the finished file.
Is annotating a PDF the same as editing its actual text?
No - annotation adds markup on top of the existing page content (highlights, notes, shapes) without changing the underlying text itself, which is exactly what you want for review and feedback rather than rewriting.